Detection devices and monitoring and measurement instruments are frequently used for ascertaining the presence and/or concentration of selected gaseous chemical species in subject environments. In addition to the selected gas species of interest, these environments may contain reactive and/or corrosive chemical materials (typically gases and vapors), the exposure of a detection sensor to which will, over a period of time, result in a degradation of the performance of the sensor, and eventually its effective inoperability.
Over and above real-time degradation in sensor performance, there are other negative consequences. For instance, the sensor performance degradation can also be manifest in the shortening of the operational lifetime of chemical sensors. Thus, their ability to serve in long-term environmental monitoring applications is compromised, thereby resulting in increased operational costs and/or the disruption of replacing the sensor more frequently than otherwise would be necessary.
Because of the obstacles to long-term monitoring, detection, and measurement that are presented by harmful chemical vapors, the identification of such harmful species, the ascertainment of the mechanism by which these species attack sensor performance, and the provision of mitigating measures would be a significant advance. More specifically, prolongation of an acceptably high level of performance and extension of the lifetime of chemical sensors, despite the presence of contaminating species, would result in reduced life-cycle costs for the user and reduced warranty exposure to the manufacturer of these devices.
It would be desirable therefore to provide a system and method for achieving more robust chemical sensor operation and for mitigating performance degradation of a sensor by a contaminant in the target environment, should such contaminant be present, while maintaining conditions that would result in a concentration of a target analyte suitable for detection by the sensor device, in the event the analyte is present.
It would also be desirable to provide an apparatus for reducing the contaminating potential of a gas sample collected from a target environment before presention of the gas sample to a chemical sensor device suitable for long-term use without maintenance and with minimal power consumption.